1. Field of the Invention
The invention relates to self-adhesive addition-crosslinking silicone compositions, to addition-crosslinked silicone elastomers and to processes for preparing them.
2. Background Art
U.S. Pat. No. 5,438,094 describes self-adhesive addition-crosslinking silicone compositions comprising as crosslinkers very specific organohydropolysiloxanes (B) and as adhesion promoters (C) special compounds having at least one aliphatic unsaturated group and two phenylene residues per molecule. Organohydrosiloxanes (B) claimed are those of the formula (1), (2) or (3): R3Si (O—SiHR)nOSiR3 (1); cyclic (OSiHR)n (2); and R4−mSi(OSiHR2)m (3). In these formulae, each R is a substituted or unsubstituted monovalent hydrocarbon group, m is 3 or 4 and n is an integer of at least 3. The patent conversely describes organopolysiloxane components of the structure:Me3Si—(SiHMe)5—(OSiMe2)8—SiMe3,as not suitable for use.
With known self-adhesive addition-crosslinking silicone compositions, the adhesion, particularly to diverse plastics, is not optimal. There is therefore a need to provide new self-adhesive addition-crosslinking silicone compositions featuring improved adhesion.